Bottle Top Gnat Trap

I wanted something so simple and cheap that I could just trow it away if I wanted. These should stack nicely if needed and should be able to be printed without supports or rafts. Simplify3D tells me that I can do a fast-print of 9 of these for 79 cents which makes them 8.7 cents each.

UPDATE 2017-03-05: Uploaded new version. Ran it through NetFab and settled it to the bed. Hope this one works a bit better.